# Add knowledge and skills to Faustine Chat

Knowledge is the set of documents the assistant searches before it answers, such as policies, manuals and price lists. A skill is a text that tells the assistant what one gateway's system is and how to use it. Both apply to every chat user in the workspace.

## Before you begin

- Faustine Chat is set up for your workspace. See [Set up Faustine Chat for your team](https://docs.faustine.ai/apps/set-up-faustine-chat/).

## Add a document

1. In the portal, go to [**Faustine Chat**](https://auth.faustine.ai/go?to=%2Fapps%2Ffaustine-chat) and select **Configuration**.
2. Under **Assistant**, select [**Knowledge**](https://auth.faustine.ai/go?to=%2Fapps%2Ffaustine-chat%2Fconfiguration%3Ftab%3Dknowledge).
3. Drop the files on the upload area, or select **browse** and choose them.

A document can be a PDF, DOCX, TXT or Markdown file of up to 25 MB. Each one appears in the list with a **Processing** badge while Faustine indexes it with the workspace's [embeddings provider](https://docs.faustine.ai/workspace/embeddings/). When the badge changes to **Ready**, the assistant searches the document from the next message.

A file that is already in the list is refused with "Already uploaded".

## Delete a document

1. On the document's row, select the delete button.
2. In the dialog, select **Delete**.

The assistant stops searching the document immediately. This cannot be undone.

## Edit a gateway's skill

Faustine installs one skill for each gateway that is turned on for the chat. The skill describes the system behind the gateway, its operations, how its connections are selected and the rules that apply. The assistant reads every skill before each conversation.

To edit a skill:

1. Under **Assistant**, select [**Skills**](https://auth.faustine.ai/go?to=%2Fapps%2Ffaustine-chat%2Fconfiguration%3Ftab%3Dskills).
2. Change the text in the gateway's editor. A skill can have up to 20,000 characters.
3. Select **Save skill**.

The change applies to the next message. The skill's badge changes from **Generated** to **Edited**.

## Bring an edited skill up to date

A **Generated** skill follows its gateway: when the gateway's operations or connections change, Faustine writes the skill again. An **Edited** skill is yours and Faustine no longer changes it. When the gateway changes after your edit, the skill shows an **Outdated** badge.

To start again from the gateway's current operations and connections:

1. Select **Reinstall** on the skill.
2. In the dialog, select **Reinstall**.

> **Warning:** Reinstalling replaces the text of the skill. Your edits to it are lost. Copy them first if you want to apply them again.

## Troubleshooting

| Symptom | Cause | Fix |
| --- | --- | --- |
| A document shows **Failed** | Faustine could not read or index the file. The row shows the reason. | Delete the document, fix the file and upload it again. |
| **Skills** shows "No skill installed yet" | No gateway is turned on for the chat. | Select **Go to Gateways** and turn one on. |

## Next steps

- [Write the prompt and custom instructions](https://docs.faustine.ai/apps/chat-prompt/): describe your users and set the assistant's rules.
- [Give chat access to specific gateways](https://docs.faustine.ai/apps/chat-gateway-access/): turn on the gateways that get a skill.
- [Faustine Chat](https://docs.faustine.ai/apps/faustine-chat/): how the assistant uses gateways, knowledge and skills together.